It is known to collect the control and supply conduits in electrical devices, for example, in electrical washing machines for dishes or clothes, etc. as well as in automotive vehicles, to cable bundles or to a cable harness. In many cases such a cable harness is preformed by the manufacturer of the device or of the automotive vehicle. The individual cables are typically held together by means of an adhesive tape or by a cable band of plastic material and fixed within the interior of the device by means of a suitable retainer.
Often, a problem arises when such a cable harness is to be extended through a wall which separates two compartments from each other, e.g., the engine compartment of an automobile from the driver compartment. It is clear that the cable harness is sealed in a grommet to prevent the passage of water and air. However, the closely collected cables, which at least partially are of relatively small diameter, define small passages therebetween in the longitudinal direction of the cable bundle, thus creating a capillary effect. Despite the mentioned sealing, therefore, moisture can enter the driver compartment of an automobile from the engine compartment and thus contact the various instrumentation in the driver compartment. This may cause corrosion in the contact areas. Further, the danger of current leakages or even of a short circuit exists.
In the case of supply conduits which carry a relatively large current, the failures caused by such phenomena are relatively small. However, a plurality of electrical devices, above all the electronic components and devices used in the manufacture of automotive vehicles, are relatively sensitive. They require a small voltage, of for example 12 Volts, and an extremely small current so that changes in the current may easily lead to a falsification of the signals.
For the above reasons, considerable efforts are undertaken to seal cable harnesses in their longitudinal direction and to cut off this capillary effect.
It is known to pour a thermosetting adhesive between the individual cables of a cable harness for this purpose. It is further known to use an intumescent thermosetting adhesive and to cover the area to be sealed with a hose of heat-shrinkable plastic material. The thermosetting adhesive is cast at relatively high temperatures and cures relatively fast after coming in contact with the cable sheath, so that the danger of cavities remaining cannot be excluded. Cable harnesses which are sealed in their longitudinal direction according to the described method thus have a relatively high failure rate.